(This sounds a bit rough, and I apologize.)
Whether the offense is illegal in Canada isn't material. The relative severity of the offense also has very little effect. (These issues may come up when an individual claims asylum, but that's about it) The sole issue is: when your wife's passport is scanned, if something comes up on the background search then there is a problem. At that point, the decision as to whether or not to let your wife enter Canada is in the hands of the customs agent, and that decision is generally "No" but there is some leeway at the sole discretion of the agent.
The advice to contact the consulate is an excellent one, and I'm glad that you're doing so. They'll provide advice on how to best proceed. However, even their advice will not provide a 100% guarantee. On the day when you try to enter Canada, please be prepared to be turned back.
